KR20100058134A - System for control starting of electronic continuous variable valve device and method thereof - Google Patents

Abstract

PURPOSE: A device and a method for controlling starting of an electronic variable valve are provided to improve initial starting by reducing starting time, and to reduce exhaust gas in a low temperature. CONSTITUTION: A method for controlling starting of an electronic variable valve is as follows. When the starting of an electronic variable valve is detected, an initial value of an exhaust valve and a suction valve is figured out(S102). It is determined whether the rotation amount of an engine is reached to the revolutions per second(S104). When the rotation amount is reached to the RPS, the suction valve is maximally sparked(S105).

Description

TECHNICAL CONTROL CONTROL STARTING OF ELECTRONIC CONTINUOUS VARIABLE VALVE DEVICE AND METHOD THEREOF

The present invention relates to an electronic variable valve device, and more particularly, a start control apparatus and method for an electronic variable valve device to improve low temperature startability and shorten start time in a vehicle equipped with an electronic variable valve of a clutch type. It is about.

In general, the performance of internal combustion engines, especially gasoline engines, depends on how much air can be put into the combustion chamber during each engine cycle. To realize this, the hydraulic variable valve device is applied to the gasoline engine to adjust the valve timing and supply the appropriate air in the cylinder according to the engine condition.

The hydraulic variable valve device has a disadvantage in that, when the engine speed is low or the engine oil is low temperature, the torque of the driving device itself is increased, making it difficult to drive and the operating angle is not large.

In order to overcome the shortcomings of the hydraulic variable valve device, the introduction of an electronic variable valve device capable of widening the operating angle is being activated.

The electronic variable valve device can be largely divided into a motor driven method and an electronic clutch type drive method. Both types have faster response speeds than conventional hydraulics and do not require oil pressure, so they can be driven even at low temperatures, reducing cold start loads and enabling quick start at lower temperatures than conventional engines. There is an advantage that can be lowered.

However, the motor-driven method is applied only to a vehicle having a large displacement due to a large installation space and a high price, and the clutch type driving method is applied to a medium vehicle due to a relatively small installation space and a low price.

In order to improve fuel economy by using a clutch type electronic variable valve device, it is necessary to control the degree of overlap between the intake valve and the exhaust valve in the partial load region.

In general, fuel efficiency improvement may be realized by retarding or advancing the opening time of the intake valve while the exhaust valve closing time is perceived in the partial load region.

Hydraulic variable valve device is implemented by advancing from the stop position due to mechanical constraints in order to improve fuel economy in the partial load region. On the other hand, since the clutch type electronic variable valve device can realize a wider operating range, a higher fuel efficiency improvement can be obtained in the partial load area by perceiving a stop position more than the hydraulic variable valve device.

However, there is a disadvantage in low temperature startability due to the perception of the stop position more than the hydraulic variable valve device.

3 is a timing diagram of an intake valve and an exhaust valve of a general hydraulic variable valve device.

As shown, a typical hydraulic variable valve device has an intake valve 11C (Crank Angle) advanced at an initial stop position and an exhaust valve controls the intake and exhaust valve at the position where engine starting is best at 0CA.

After the driver turns on the key, the intake valve advances the range of about 45CA according to the engine driving condition of the vehicle, and the exhaust valve senses the range of about 45CA while controlling the engine operability and fuel economy in the best position. do.

Therefore, the conventional hydraulic variable valve device starts the engine in the form of an open loop by predicting only the amount of fuel compared to the amount of air at the start of the engine since the intake and exhaust valves are stopped at the best starting condition of the engine.

In contrast, the clutch type electronic variable valve device has a wide intake valve and exhaust valve cam timing diagram to realize fuel efficiency improvement under partial load operation conditions.

 As shown in FIG. 4, since the intake valve is 46CA advanced and the exhaust valve is 0CA at the initial stop position of the clutch type electronic variable valve device, the operating section is wider than the hydraulic variable valve device and the intake valve opens quickly. Under Lap section is widened.

The control logic of the conventional hydraulic variable valve device checks the engine state, the state of the sensor and the actuator when the starter key is turned on, and simultaneously completes the engine crank and cam synchronization. The intake and exhaust cams are controlled using the calculated values.

Therefore, when the control logic of the conventional hydraulic variable valve device is applied to an electronic variable valve device of the clutch type, when the engine is started at a low temperature, there is a problem in that the starting is not stopped due to combustion instability in the cylinder.

The present invention has been invented to solve the above problems, the object of which is to open the cam timing of the intake valve by applying the air coolant temperature and the start time and the air volume model mapping value according to the change of the cam when the vehicle starts Loop to control the cam perception time to improve the startability.

In addition, another object of the present invention is to learn the stop position of the intake valve and the exhaust valve in the fuel cut-off section in which the intake valve and the exhaust valve are not operated in order to implement a faster start to apply the conditions to the future start.

Starting control device of the electronic variable valve device according to a feature of the present invention for achieving the above object,

A driving information detection unit detecting overall state information of the vehicle;

And a controller for controlling the electronic variable valve device to maximize the intake cam timing at the maximum perception when the engine speed reaches the ultra-high speed in the cranking according to the start-up.

In addition, the start control method of the electronic variable valve device according to a feature of the present invention,

Reading initial values of the intake valves and exhaust valves when a start-on request is detected, and determining whether the engine rotational speed according to the cranking has reached an extremely high rotational speed;

Advancing the maximum perceiving intake valve to the maximum when the ultra-high speed has been reached;

And controlling the ignition timing and the fuel supply amount according to the intake air amount and the cooling water temperature to start the engine.

By the above-described configuration, the present invention can improve the initial starting performance by shortening the starting time in the engine with the clutch type electronic variable valve device, and reducing the exhaust gas at a low temperature and stabilizing combustion according to the fast starting time. You can expect the effect to make.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

Since the present invention can be implemented in various different forms, the present invention is not limited to the exemplary embodiments described herein, and parts not related to the description are omitted in the drawings in order to clearly describe the present invention.

1 is a view schematically showing a start control device of an electronic variable valve device according to an embodiment of the present invention.

The present invention includes a driving information detection unit 100 and the control unit 200, the electronic variable valve device 300, the ignition device 400 and the fuel injection device 500.

The driving information detector 100 detects general state information of the vehicle and provides the information to the controller 200.

The operation information detection unit 100 operates the start key detection unit 101 for detecting the trigger contact of the ignition key, the engine speed detection unit 103 for detecting the engine speed from the angular displacement of the crankshaft, the intake valve and the exhaust valve. The cam angle detector 105 detects the angle of the cam, the air amount detector 107 detects the amount of air sucked into the engine, the water temperature detector 109 detects the temperature of the coolant circulating in the engine, and the accelerator pedal. And a throttle opening degree detecting unit 111 for detecting the opening degree of the operated throttle valve and a vehicle speed detecting unit 113 for detecting the current traveling vehicle speed.

The control unit 200 inputs the trigger contact of the ignition key, the engine speed, the cam angle, the intake air amount, the coolant temperature, the opening amount of the throttle valve, and the vehicle speed from the operation information detection unit 100, and the electronic variable valve according to the input information. The control signal for adjusting the valve timing on the side of the apparatus 300, the signal for controlling the ignition for the ignition device 400, and the signal for controlling the fuel injection amount for the fuel injection device 500 are output.

The control unit 200 starts cranking for starting the engine according to the detection of the starting contact of the ignition key. When the engine speed reaches the maximum speed in the cranking state, the intake cam timing is maximum perceptible for a quick start. Advance to maximum.

At this time, the output signal and the holding time when advancing the intake cam timing to the maximum apply values mapped according to the cooling water temperature as shown in Table 1 and Table 2 below.

Cooling water temperature (℃) -25 -10 0 20 30 50 60 70 90 Output signal (duty ratio%) 90 90 80 60 60 60 60 60 60

Cooling water temperature (℃) -25 -10 0 20 30 50 60 70 90 Holding time (sec) 6 4 2 1.5 1.5 1.5 1.0 1.0 1.0

The maximum advance maintenance time of the intake valve determined as shown in Table 2 above is not applied when the maximum rotation speed at which the engine rotation speed is the full rotation speed when the engine is started is not applied. The timing of the cam according to the state is controlled.

In addition, the controller 200 may control an ignition signal for controlling the ignition device 400 and a fuel injection control signal for controlling the fuel injection device 500 according to the intake air amount and the coolant temperature included in the information of the operation information detection unit 100. Output

The operation of the present invention including the above-described functions will be described in more detail with reference to FIG. 2.

When the trigger contact of the ignition key is selected as the starting contact point and detected by the control unit 200 while the engine to which the clutch type electronic variable valve device is applied is detected (S101), the control unit 200 detects the cam angle detection unit 105. The initial values of the intake valve and the exhaust valve are read by analyzing the information (S102), and general operation information such as the coolant temperature, the engine speed, the opening degree of the throttle valve, and the vehicle speed are read (S103).

When the starting contact point of the ignition key is detected as described above, the control unit 200 starts the cranking by operating a start motor (not shown), and determines whether the engine speed reaches the maximum speed according to the cranking (S104).

If the engine speed has not reached the super-speed, the process returns to step S103. If the engine speed has reached the super-speed, the intake cam timing which is the maximum perception for the quick start is advanced to the maximum (S105).

At this time, the output signal and the holding time at the time of advancing the intake cam timing to the maximum are applied according to the cooling water temperature as shown in Table 1 and Table 2 above.

Thereafter, the amount of intake air is detected, and then an ignition signal for controlling the ignition device 400 and a fuel injection control signal for controlling the fuel injection device 500 are generated and output, including the information of the coolant temperature (S106) (S107). .

In the control state as described above, it is determined whether the engine speed reaches the maximum starting speed (S108), and if the maximum speed is not reached, the process returns to the process of S106, and if the maximum starting speed has been reached, it is determined whether the engine engine speed exceeds the set time. (S109).

If it does not last longer than the set time in the determination of S109 is returned to the process of S106, and if the engine speed has reached the maximum starting speed and lasts longer than the set time, it is determined that the engine start is successful (S110).

Thereafter, the driving state of the vehicle is detected (S111), and it is determined whether the fuel cutoff condition according to the acceleration pedal is turned off (S112). If the fuel cutoff condition is not satisfied, the process returns to the step S111 and if the fuel cutoff condition is satisfied. The ignition signal is turned off and at the same time the fuel supply is cut off to improve fuel economy (S113).

At this time, the controller 200 reads the information of the cam angle detector 107 to learn the stop positions of the intake valve and the exhaust valve (S114) and stores them in a non-volatile memory (not shown) for application to initial start-up. (S115).

As described above, the stop position learning of the intake valve and the exhaust valve is executed every time the fuel shut-off condition is entered, and when the engine is turned off, the initial position of the learned cam timing is stored in a non- volatile region (not shown) to store the next initial position. Used at startup.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It is included in the scope of rights.

1 is a view schematically showing a low temperature start device of an electronic variable valve device according to an embodiment of the present invention.

Figure 2 is a flow chart for performing a low temperature start of the electronic variable valve device according to an embodiment of the present invention.

3 is a timing diagram of an intake and exhaust valve cam in a stopped state and a started state of the hydraulic variable valve device.

4 is a timing diagram of an intake / exhaust valve cam in a stopped state and a started state of the electronic variable valve device.

<Explanation of symbols for the main parts of the drawings>

100: operation information detection unit 200: control unit

300: electronic variable valve device 400: ignition device

500: fuel injection device

Claims (7)

A driving information detection unit detecting overall state information of the vehicle; A control unit for controlling the electronic variable valve device to advance the maximum perceiving intake cam timing to the maximum when the engine speed reaches the ultra-high speed in the cranking according to the start-up; Starting control device of the electronic variable valve device comprising a. The method of claim 1, The operation information detection unit may include a start key detection unit detecting a trigger contact of an ignition key; An engine speed detector for detecting engine speed from an angular displacement of the crankshaft; A cam angle detector for detecting a cam angle for operating the intake valve and the exhaust valve; An air amount detector for detecting an air amount sucked into the engine; A water temperature detector detecting a temperature of the cooling water; A throttle opening degree detector for detecting an opening degree of a throttle valve; A vehicle speed detector detecting a vehicle speed; Starting control device of the electronic variable valve device comprising a. The method of claim 1, The control unit is a start control device of the electronic variable valve device to apply the output signal and the holding time mapped in accordance with the cooling water temperature when advancing the intake cam timing. The method of claim 1, The control unit is a start control device of the electronic variable valve device that applies to the next start by learning and storing the stop position of the intake valve and the exhaust valve when entering the fuel cut-off condition. Reading initial values of the intake valves and exhaust valves when a start-on request is detected, and determining whether the engine rotational speed according to the cranking has reached an extremely high rotational speed; Advancing the maximum perceiving intake valve to the maximum when the ultra-high speed has been reached; Starting the engine by controlling the ignition timing and the fuel supply amount according to the intake air amount and the cooling water temperature; Start control method of an electronic variable valve device comprising a. The method of claim 5, And a stop position of the intake valve and the exhaust valve is learned and stored in the nonvolatile memory when the fuel cutoff condition is entered in the engine start-on state, and the stop position information stored in the next start is applied. The method of claim 5, The advance control of the intake valve according to the arrival of the ultra-high rotational speed is the start control method of the electronic variable valve device to apply the output signal and the holding time mapped in accordance with the cooling water temperature.

Images